Consumers' love of hi-tech gadgets is set to undermine attempts to curb the UK's carbon emissions, the Energy Saving Trust (EST) claimed today.

The proliferation of home entertainment equipment such as flatscreen TVs, digital radios and laptops in homes means that by 2020 this type of technology will account for 45% of domestic electricity use.

This means 14 power stations will be required just to power equipment used for communication and entertainment, the EST said in its report the Ampere Strikes Back.

The growth in energy use is a result of changing lifestyles, which means there are more households in the UK, and the demands of new equipment, which tend to be more energy intensive than older products, contrary to the belief of 54% of those questioned.

The running cost of today's plasma and LCD screen TVs can be as much as three times that of traditional cathode ray tube sets. The largest domestic plasma TV on the market - with a massive 103in screen - has a power rating of 1.5kw, which means watching it uses as much energy as leaving 25 lightbulbs on.

In addition, rather than disposing of old TVs and DVD players consumers are moving them into other rooms in the house where they may be used at the same time as the new equipment.

"Products are being used in ways that were undreamt of just a few years ago," said Philip Sellwood, chief executive of the EST.

"With trends such as listening to the radio through TV and PC on the increase, it's highly unlikely that consumers realise that this uses far more energy than conventional means, or that some digital radios use almost as much energy when considered switched off at the unit as they do while switched on, while a new flat panel TV can use up to three times more electricity than a 'traditional' TV."

Mr Sellwood urged consumers to think about their energy use and turn off equipment that was not needed, and to rein in their impulse to hoard unwanted items.

"By being more 'switched on' with our appliances the average household could save £37 a year through avoided standby use alone, and some of the 2020 energy burden projections could be curbed," he added.

UK consumers spend more than £12bn a year on home IT and electronics, the EST said - more than anyone else in Europe.

The average household spends £500 a year on such goods, and by 2020 the running costs across the UK could total more than £4bn a year - £607m of which will be spent on leaving items on standby.